Such cryostats are used in order to cut frozen specimens with a microtome for subsequent viewing with a microscope. The preparations to be cut are cooled to a specific predefined temperature, the temperatures in this context generally being between −10° C. and −50° C. In order to achieve these temperatures, an appropriately dimensioned refrigeration device, with which a control system and a central power supply are associated, is provided in the cryostat.
To ensure a constant temperature, the microtomes are arranged in complexly encapsulated cryostat chambers, and the latter are correspondingly cooled with the refrigeration device.
The frozen specimens are cut using a microtome arranged in the cryostat chamber, and then transferred from the knife or knife holder onto a specimen slide. It has proven advantageous in this context if the specimen slides are temperature-controlled or preheated in order to ensure reliable transfer of the cut specimen. If the specimen slides are too cold, the section does not thaw out on the specimen slide, and the danger exists that there will be no adhesion and the section will then fall off.
Heating plates are available commercially, but they are always embodied as a separate unit, have a corresponding space requirement, and must be arranged separately from the cryostat.